[Arm64/Unix] Enable FEATURE_USE_SOFTWARE_WRITE_WATCH_FOR_GC_HEAP (#11375)

* [Arm64/Unix] Enable FEATURE_USE_SOFTWARE_WRITE_WATCH_FOR_GC_HEAP
* [Arm64/Unix] Enable FEATURE_MANUALLY_MANAGED_CARD_BUNDLES

Author: sdmaclea

clrdefinitions.cmake

@@ -177,10 +177,10 @@ if(CLR_CMAKE_PLATFORM_UNIX_AMD64)
   add_definitions(-DFEATURE_UNIX_AMD64_STRUCT_PASSING)
 endif (CLR_CMAKE_PLATFORM_UNIX_AMD64)
 add_definitions(-DFEATURE_USE_ASM_GC_WRITE_BARRIERS)
-if(CLR_CMAKE_PLATFORM_ARCH_AMD64 AND NOT WIN32)
+if((CLR_CMAKE_PLATFORM_ARCH_AMD64 OR CLR_CMAKE_PLATFORM_ARCH_ARM64) AND NOT WIN32)
   add_definitions(-DFEATURE_MANUALLY_MANAGED_CARD_BUNDLES)
   add_definitions(-DFEATURE_USE_SOFTWARE_WRITE_WATCH_FOR_GC_HEAP)
-endif(CLR_CMAKE_PLATFORM_ARCH_AMD64 AND NOT WIN32)
+endif((CLR_CMAKE_PLATFORM_ARCH_AMD64 OR CLR_CMAKE_PLATFORM_ARCH_ARM64) AND NOT WIN32)
 if(WIN32)
     add_definitions(-DFEATURE_VERSIONING_LOG)
 endif(WIN32)

src/jit/target.h

@@ -1573,7 +1573,7 @@ typedef unsigned short regPairNoSmall; // arm: need 12 bits
 
   #define RBM_CALLEE_SAVED        (RBM_INT_CALLEE_SAVED | RBM_FLT_CALLEE_SAVED)
   #define RBM_CALLEE_TRASH        (RBM_INT_CALLEE_TRASH | RBM_FLT_CALLEE_TRASH)
-  #define RBM_CALLEE_TRASH_NOGC   (RBM_R12|RBM_R13|RBM_R14|RBM_R15)
+  #define RBM_CALLEE_TRASH_NOGC   (RBM_R12|RBM_R13|RBM_R14|RBM_R15|RBM_IP1)
   #define REG_DEFAULT_HELPER_CALL_TARGET REG_R12
 
   #define RBM_ALLINT              (RBM_INT_CALLEE_SAVED | RBM_INT_CALLEE_TRASH)

src/vm/arm64/asmhelpers.S

@@ -217,6 +217,7 @@ LEAF_END ThePreStubPatch, _TEXT
 //   x13  : incremented by 8
 //   x14  : incremented by 8
 //   x15  : trashed
+//   x17  : trashed (ip1) if FEATURE_USE_SOFTWARE_WRITE_WATCH_FOR_GC_HEAP
 //
 WRITE_BARRIER_ENTRY JIT_ByRefWriteBarrier
 
@@ -236,6 +237,7 @@ WRITE_BARRIER_END JIT_ByRefWriteBarrier
 //   x12  : trashed
 //   x14  : incremented by 8
 //   x15  : trashed
+//   x17  : trashed (ip1) if FEATURE_USE_SOFTWARE_WRITE_WATCH_FOR_GC_HEAP
 //
 WRITE_BARRIER_ENTRY JIT_CheckedWriteBarrier
     PREPARE_EXTERNAL_VAR g_lowest_address, x12
@@ -262,6 +264,7 @@ WRITE_BARRIER_END JIT_CheckedWriteBarrier
 //   x12  : trashed
 //   x14  : incremented by 8
 //   x15  : trashed
+//   x17  : trashed (ip1) if FEATURE_USE_SOFTWARE_WRITE_WATCH_FOR_GC_HEAP
 //
 WRITE_BARRIER_ENTRY JIT_WriteBarrier
     dmb  ST
@@ -310,6 +313,21 @@ LOCAL_LABEL(shadowupdateend):
     ldp  x12, x13, [sp],#16
 #endif
 
+#ifdef FEATURE_USE_SOFTWARE_WRITE_WATCH_FOR_GC_HEAP
+    // Update the write watch table if necessary
+    PREPARE_EXTERNAL_VAR g_sw_ww_enabled_for_gc_heap, x12
+    ldrb w12, [x12]
+    cbz  x12, LOCAL_LABEL(CheckCardTable)
+    PREPARE_EXTERNAL_VAR g_sw_ww_table, x12
+    ldr  x12, [x12]
+    add  x12, x12, x14, lsr #0xc  // SoftwareWriteWatch::AddressToTableByteIndexShift
+    ldrb w17, [x12]
+    cbnz x17, LOCAL_LABEL(CheckCardTable)
+    mov  w17, #0xFF
+    strb w17, [x12]
+#endif
+
+LOCAL_LABEL(CheckCardTable):
     // Branch to Exit if the reference is not in the Gen0 heap
     //
     PREPARE_EXTERNAL_VAR g_ephemeral_low, x12
@@ -333,6 +351,21 @@ LOCAL_LABEL(shadowupdateend):
 LOCAL_LABEL(UpdateCardTable):
     mov  x12, 0xFF 
     strb w12, [x15]
+
+#ifdef FEATURE_MANUALLY_MANAGED_CARD_BUNDLES
+    // Check if we need to update the card table
+    PREPARE_EXTERNAL_VAR g_card_bundle_table, x12
+    ldr  x12, [x12]
+    add  x15,  x12, x14, lsr #21
+    ldrb w12, [x15]
+    cmp  x12, 0xFF
+    beq  LOCAL_LABEL(Exit)
+
+LOCAL_LABEL(UpdateCardBundle):
+    mov  x12, 0xFF
+    strb w12, [x15]
+#endif
+
 LOCAL_LABEL(Exit):
     add  x14, x14, 8
     ret  lr  

src/vm/arm64/stubs.cpp

@@ -1317,6 +1317,19 @@ void StompWriteBarrierResize(bool isRuntimeSuspended, bool bReqUpperBoundsCheck)
     return;
 }
 
+#ifdef FEATURE_USE_SOFTWARE_WRITE_WATCH_FOR_GC_HEAP
+void SwitchToWriteWatchBarrier(bool isRuntimeSuspended)
+{
+    return;
+}
+
+void SwitchToNonWriteWatchBarrier(bool isRuntimeSuspended)
+{
+    return;
+}
+#endif // FEATURE_USE_SOFTWARE_WRITE_WATCH_FOR_GC_HEAP
+
+
 #ifdef DACCESS_COMPILE
 BOOL GetAnyThunkTarget (T_CONTEXT *pctx, TADDR *pTarget, TADDR *pTargetMethodDesc)
 {